[krbdev.mit.edu #7926] AutoReply: 1.12 breaks gssapi mechanisms that recursively call into libgssapi

Sam Hartman via RT rt-comment at krbdev.mit.edu
Wed Jun 4 13:05:30 EDT 2014


Here's a patch to fix the problem:

>From ed4d5c8679e5b162b8cf20c0f4d8ddb6d241f7da Mon Sep 17 00:00:00 2001
From: Sam Hartman <hartmans at debian.org>
Date: Wed, 4 Jun 2014 12:06:27 -0400
Subject: Do not loop on add_cred_from and other new methods

Several new GSS-API methods were added but GSSAPI_ADD_METHOD was
called to add them rather than GSSAPI_ADD_METHOD_NOLOOP.  This means
that the implementation from the GSS-API mechglue would be used if the
mechanism had no implementation.  As a result, the mechglue will call
into itself exhausting the call stack in an endless loop when one of
these methods is called.

ticket: 7926
---
 src/lib/gssapi/mechglue/g_initialize.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/lib/gssapi/mechglue/g_initialize.c b/src/lib/gssapi/mechglue/g_initialize.c
index 7fab03d..f997096 100644
--- a/src/lib/gssapi/mechglue/g_initialize.c
+++ b/src/lib/gssapi/mechglue/g_initialize.c
@@ -731,11 +731,11 @@ build_dynamicMech(void *dl, const gss_OID mech_type)
         GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_inquire_mech_for_saslname);
         /* RFC 5587 */
         GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_inquire_attrs_for_mech);
-	GSS_ADD_DYNAMIC_METHOD(dl, mech, gss_acquire_cred_from);
-	GSS_ADD_DYNAMIC_METHOD(dl, mech, gss_store_cred_into);
+	GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_acquire_cred_from);
+	GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_store_cred_into);
 	GSS_ADD_DYNAMIC_METHOD(dl, mech, gssspi_acquire_cred_with_password);
-	GSS_ADD_DYNAMIC_METHOD(dl, mech, gss_export_cred);
-	GSS_ADD_DYNAMIC_METHOD(dl, mech, gss_import_cred);
+	GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_export_cred);
+	GSS_ADD_DYNAMIC_METHOD_NOLOOP(dl, mech, gss_import_cred);
 	GSS_ADD_DYNAMIC_METHOD(dl, mech, gssspi_import_sec_context_by_mech);
 	GSS_ADD_DYNAMIC_METHOD(dl, mech, gssspi_import_name_by_mech);
 	GSS_ADD_DYNAMIC_METHOD(dl, mech, gssspi_import_cred_by_mech);



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